pictures of the locations of the treasure chests. 26% of chest locations added so far, with all of Area 1 and 2 including the golden chests.
Introduction
as of working on area #3 I have realized that the updates making some stages easier has somewhat impacted the layout of the paths leading up to chests so this guide might not even be accurate by the time I complete it. I need to get some sleep now, but I will finish adding the chests I have collected to the guide tomorrow which will bring it up to at least 92% complete. I doubt anyone will read this before I get back to working on it, but if you do please comment with the world 5 chests, as I have found only the three that were added to this guide.
Area #1
Secret wall to the left.

1-2:
Switch in a crawlspace to the left which lowers the acid revealing another switch with opens the door to the chest.


1-3:
Button in the top left which lowers the quicksand and reveals the chest.

1-4:
The chest is underground accessed by pulling the box to the right. The super chest is behind a trial hidden in a wall to the left of the regular chest.


1-5:
Pull down on the chain to lower the elevator to the chest, it is located past some swinging rope jumps.


1-6:
Secret passage in a secret passage.

1-7:
Hidden through the spikes(You can walk through them if you start at their level).

1-8:
Through multiple breakable ceilings. I believe you have to go past this on the reverse level so im not including pictures of all the ceilings you can break.
Area #2
Secret tunnel in the roof to get on top of the hill. Then you need to run up the wall to the hidden area with the chest. (You can also float above campfires by gliding which could have been nice to know before I completed the game)


2-2:
Stand between the panes of glass as they regenerate in order to climb up to the chest area. The hidden path at the chest area is used in the return trip and is (probably) inaccessible with Leo.


2-3:
To the left at the bottom of the pit you need to jump over.

2-4:
In a hidden area to the right which you can use coyote time to jump to.

2-5:
Push the box to hold the button to the left opening the chest area.

On the return trip with Nara you can go up through the ceiling and go to the right past the credits house to reach this areas super chest.
2-6:
You can jump through the ceiling in a few spots to reach the chest room.

You can also jump through the ceiling in the chest room by jumping of your hat and then head to the right to reach the golden chest, but I am not sure if you can get it with Leo.

2-7:
You need to either jump onto the platforms above the tunnel as you break them, or collect this on the return trip with Nara.
Or somehow get into this tunnel on the room to the left with Leo, which Is probably impossible as its meant to be accessed with Nara.
2-8:
You can access the chest room through a secret tunnel, where you will have to ride on top of some boulders to reach the chest.
You might also be able to reach the chest in the previous room with Leo if you can somehow get into the tunnel in the roof early.

Area #3
Inside the tower to the right.

3-2:
In a secret ceiling path, has been simplified by the update.
Area #4
Area #5
Button in top right that activates a trapdoor to the chest in the top left.

5-2:Chest in secret wall at the top right.
5-3:The real chest is the one in the top left.
super chest accessed by wall-jumping through the top center gives the sunflower.
5-4: